As communication network operators and user organizations evaluate their two-way radio needs for the future, many are reaching some similar conclusions: radio spectrum is becoming more congested and regulators are requiring the networks to do more with less, the demand for data transmission is more pronounced and often unachievable in narrow-band systems, systems need increased functionality, secure communication is a growing necessity, and improved digital voice quality is essential over more of the coverage area.
It will be appreciated that upgrading a communications network is a major undertaking in terms of time, energy and expense. A number of possible solutions are available, including the digital technologies that are now available.
A radio frequency (RF) site becomes congested due to limited bandwidth and heavy load. Conventional mechanisms based on site load to prevent congestion can only delay the low privilege attempts by increasing access threshold and allowing the low privilege attempts to load the site as soon as the threshold is lowered again. These mechanisms fail to avoid congestion when the RF site is experiencing a sustained heavy load because the delayed attempts will make the site load even heavier when they are back to compete with the “normal” attempts for resources. In addition, existing mechanisms to indicate high load will cause a mobile communication device to leave the cell, which may not be desirable as it may thereafter cause congestion on a neighbor cell.
Accordingly, there is a need for a method for providing control of push-to-talk communication within a wireless communication system to prevent congestion of a radio frequency site.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.